Patent document WO2007/028035 discloses a system for communicating information within the body of an animal. The system comprises a first device comprising a transmitter configured to transmit a signal via a quasi electrostatic coupling to the body of the patient and a second device comprising a receiver configured to receive the transmitted signal via a quasi electrostatic coupling to the body of the patient. The data is transmitted using a carrier signal having a carrier frequency typically in the range of about 10-100 KHz. Data is encoded using known modulation techniques such as amplitude modulation, frequency modulation or phase modulation of the carrier signal.
The solution disclosed in WO2007/028035 may not be well suited for electro-stimulation devices as the stimuli can contaminate the data signals. This can result in unreliable data transmission. Further, the data signal generation may require additional electronics. Dedicated signal generation circuits may be needed to generate the data carrying signal and dedicated transmit/receive electrode pairs may be needed to transmit and receive the data signals.
Hence, it would be advantageous to have an improved system that can reliably communicate information between two medical devices implanted within the body of a subject.